Crashes (that can be reliably reproduced) should be way easier to debug than memory leaks.

a) build a `debug` version of node (building node from source creates a node_g version which is a debug version)

b) build a `debug` version of all of the c++ addons in your node_modules folder (node-gyp build -d for each addon)

c) start gdb with the debug version of node: `gdb ./node_g`

d) in gdb, run your node script using `run <script.js>` -- add any other options

e) wait for it to crash, and then type `bt` - you'll see the location of the crash which should give you a good starting place.